DE 198 37 460 A1 describes, for example, a method for the real-time charging of telecommunications connections if a subscriber is in a foreign country and is therefore outside the home network. DE 198 37 460 A1 thereby describes a telecommunications connection between a terminal belonging to a telecommunications subscriber, who is abroad with the terminal, and the telecommunications provider which operates a server in the home country. So-called “roaming” thereby describes the possibility for the telecommunications subscriber to automatically receive or make calls abroad and to be able to use other mobile radio services in a foreign network.
It has previously been described in the case of roaming or is conventional practice for a time stamp of the home network of the respective telecommunications provider to generally appear when incoming calls are diverted to a mailbox and/or for the time stamp to be communicated to the telecommunications subscriber by an automatic announcement. The time stamp thereby relates to the date, and in particular, for example, to the time in the home country at which the call arrived in the mailbox.
The benefit of this information is clear for telecommunications subscribers in the time zone of the home country. The telecommunications subscriber immediately knows when the call arrived in the mailbox based on this information with the result that it is possible to easily determine what time has elapsed since the call was made and, for example, when the best time to call back the subscriber who made the mailbox recording would be. A telecommunications subscriber in a different time zone must, however, calculate this information from the time difference to the time zone of the home country.
WO 99/39499 A2 describes a method which assigns both an item of information relating to a first time zone in which the telecommunications subscriber is located and an item of information relating to a second time zone in which the caller was located to the messages stored in the mailbox. The information can be read from the time stamps of the stored messages.
At least one item of information relating to the first time zone and to the second time zone is transmitted to the telecommunications subscriber when a mailbox provided by the telecommunications provider is used.